An analysis of silicone gel-filled breast implants: Diagnosis and failure rates

This retrospective review analyzed 180 women who underwent explantation of 357 silicone gel-filled breast implants from September of 1991 to January o f 1995. Implant status, including shell integrity and implantation times, w as determined at the time of explantation. The age range of the patients wa s 25 to 75 years, with a mean age of 47 years. The age of the implants rang ed from 0.5 to 24 years, with a mean age of 10.5 years. Of the 292 implants with known and documented integrity status, there were 102 intact, 76 unruptured with signs of leakage, and 114 ruptured. The freq uency of implant rupture significantly increased with implant age. The aver age age of rupture was 13.4 years. The average age of signs of leakage was 10.1 years. There were no significant differences in failure rates among th e implant types of four manufacturers. Analysis of both mammography and magnetic resonance imaging (MRI) as diagno stic modalities for differentiating intact implants, implant leakage, and i mplant rupture was performed. Standard mammography was less reliable in dia gnosing implant leakage or rupture (sensitivity, 55 percent; specificity, 6 9 percent) than MRI (sensitivity, 72 percent; specificity, 82 percent). In conclusion, implant rupture occurred at a significantly increasing rate with implant age (10 to 15 years). These findings were independent of impla nt type or manufacturer. Mammography alone is a below-average diagnostic to ol for detecting leakage or rupture, whereas MRI is a more accurate modalit y.